There are numerous self-propelled machines or apparatus available on the market both of the gasoline powered variety and electric powered variety which are used in gardening and in the maintenance of lawns. In such machines which have means providing self-propelled movement during both forward and reverse operation thereof, or like, various complex systems are employed which may utilize chain drives, special gear systems, complex clutching mechanisms, complicated belt arrangements using belts which are required to slip most of their operating life, or various combinations of these complex systems whereby the cost to provide such self-propelled forward and reverse movement is substantial.